Analisis Pengujian Tangen Delta Pada Bushing Trafo 150/20 Kv 60 Mva Di Gardu Induk Karet Lama

Abstract

ABSTRAK

Transformator daya merupakan peralatan penting dalam sistem tenaga listrik. Terdapat komponen utama yang perlu mendapatkan perhatian khusus pada transformator yaitu bushing. Bushing merupakan sarana penghubung antara belitan dengan jaringan luar. Untuk mengetahui kondisi bushing transformator dapat diketahui  Pemburukan atau kegagalan isolasi buhing dapat menyebabkan kegagalan operasi bahkan kerusakan pada transformator. Metode untuk mengetahui kondisi bushing yaitu menggunakan metode pengujian tangen delta dimana pengujian ini bertujuan untuk mengetahui kondisi isolasi yakni kondisi isolasi pada C1 (isolasi antara konduktor dengan center tap) yang menggambarkan kondisi isolasi kertas bushing. Berdasarkan hasil pengujian tangen delta  bushing trafo dan pembuktian hasil uji menggunakan rumus perhitungan tangen delta bushing trafo diperoleh bushing transformator phasa s di Gardu Induk Karet Lama sudah tidak layak beroperasi, hasil uji 1,32%. Mengacu pada standar hasil uji tangen delta bushing transformator, yaitu SKDIR520 PT PLN (IEC 60137 – DF tan δ) batas nilai tangen delta melebihi 1%, maka bushing transformator dikatakan dalam kondisi buruk sehingga perlu dilakukan penggantian. Terdapat kecenderungan penurunan kondisi bushing yang memburuk dalam kurun waktu tiga tahun terakhir. ,Atas dasar itulah dilakukan penggantian bushing transformator tenaga sisi primer fasa S di Gardu Induk Lama. Setelah dilakukan penggantian bushing didapatkan nilai tangen delta atau dissipation factor (faktor disipasi) sebesar 0,29% yang menunjukkan bahwa bushing dalam kondisi baik dan dapat dioperasikan kembali.

 Kata Kunci : Transformator, Bushing, Tangen Delta

ABSTRACT

The power transformer is an important piece of equipment in the electric power system. There is a main component that needs special attention on the transformer, namely the bushing. Bushing is a means of connecting the winding with the external network. To determine the condition of the transformer bushing, it can be seen Deterioration or failure of buhing insulation can cause operation failure and even damage to the transformer. The method to determine the condition of the bushing is using the tangent delta test method where this test aims to determine the condition of the insulation, namely the insulation condition at C1 (insulation between the conductor and the center tap) which describes the condition of the bushing paper insulation. Based on the test results of the tangent delta bushing of the transformer and the proof of the test results using the formula for calculating the tangent delta bushing of the transformer, it is found that the s-phase transformer bushing at the Old Karet Substation is no longer feasible to operate, the test result is 1.32%. Referring to the standard results of the transformer bushing tangent delta test, namely SKDIR520 PT PLN (IEC 60137 – DF tan ) the limit value of the delta tangent exceeds 1%, the transformer bushing is said to be in bad condition so it needs to be replaced. There is a downward trend in bushing conditions that have worsened in the last three years. On this basis, the bushing of the primary side of the S-phase power transformer was replaced at the Old Substation. After replacing the bushing, the tangent delta value or dissipation factor is 0.29% which indicates that the bushing is in good condition and can be operated again

Keywords : Transformer, Bushing, Tangent Delta